Aperture Setting- Critical & Super Critical Aperture
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| f-5.6 |
Before starting a discussion on aperture settings, we should know the DOF or depth of field of the frame. Depth of field is basically the focus area on the frame. Sometimes we need to focus only on the subject and sometimes we need to focus throughout the frame. This focus area is called depth of field or in short DOF. Basically, the pin point focus area which creates a clear differentiation from the blur background and foreground is known as depth of field of the frame or your composition. This DOF plays the main role in the frame where you could create a clear cut of your subject from background or the foreground. We can decide this focus area from a pin point area to all over the frame which can be decided by the aperture setting in your camera. Not only the depth of field is concerned, other aspects of photography are also affected by aperture that we can change through the aperture.
For setting the aperture you should set your camera in aperture priority mode or manual mode. You can change the aperture value only through these two modes. The unit of aperture is symbolized by the small ‘f’ which you will get on the camera control panel. Look at the top of the right side and after the setting of mode with the help of thumb dial or front control dial you can adjust the aperture. Increase or decrease or precisely adjust the f value and the f value will be indicated on the control panel. But you should know the lenses because the aperture diaphragm is inside the lens. The shutter speed is inside the camera body as well. Each and every lens indicates its lowest aperture or highest aperture on the body of it. Before using or controlling the aperture of a lens you should know the f value of your camera. The camera cannot decrease the f value more than that. The effect of f value also depends on the camera body i.e. Fx body or Dx body.
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| f-1.4 |
You
will get DOF all over the frame in the lowest aperture and zoom out condition
or in wide part basically in the DX body but in FX format you won’t get that
effect automatically. You have to adjust f value in your FX camera but if you
zoom then both are the same for the f value. The f value is more effective
through all the prime lenses. Always remember when you zoom in, the focus area
gradually becomes shallow and at that time according to your subject depth you
have to increase aperture or f value. For wildlife photography or product
photography it's very necessary. For landscape photography we need DOF
throughout the frame so we have to increase the f value. But increasing the f
value decreases the shutter speed. Sometimes we need a tripod for the stability
of the camera.
The
increasing or decreasing of the f value depends on some aspect ratio according
to the lenses’ highest or lowest aperture. Here you should notice that I’m not
talking about the highest aperture like f22 or f32 but the highest aperture
when you zoom the lens. I have mentioned that if you zoom, your DOF area will
be shallow. During zooming most of the zoom lenses' aperture increases two
steps and that aperture will be fixed as the lowest f value at that point.
The two basic points are here for every lens where we get the maximum effects or maximum sharpness of the subject. Simply if we increase or decrease the f value it will not work. The two basic points are critical aperture and super critical aperture.
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| f-7.1 Critical Aperture- Critical aperture is the two steps
ahead from the highest aperture of a particular lens like if a lens consists of
the aperture value f3.5-5.6 then f5.6 will be the highest aperture of that
lens. You can increase the value with the dial control by using only the two
strokes that will be the two steps ahead from the highest aperture f7.1. Most
of the time I use this f value as it gives the highest shallow subject depth on
the frame. For portrait, street, product, fashion this is the ideal for all and
also you will get enough shutter speed as well for freezing your subject and to
avoid the shaky images. Eighty percent of the time I use this f value for the
most of the photography. Super Critical Aperture- The five steps ahead from the critical aperture or mostly the double of the critical aperture is called super critical aperture. Near about f11 for the particular lens we have taken as an example. In this setting we actually get the highest DOF throughout the frame. But the main problem is the camera reduces the shutter speed because of shallow aperture. So, there is a chance to get shaky images when you do hand held photography. You can increase the ISO where the sensor sensitivity will increase and the shutter speed will be increased and you will get rid of shaky images. But in low range dslr increasing the ISO means increasing the unwanted noise throughout the frame. The recommendation is to use a tripod for this setting. Mainly we need this aperture setting for group photos or landscape photography. During group photos so many faces are there in so many layers and we need each and every face in focus. For the landscape so many elements are there in so many distances and we need each and every part in focus, we should set the f value in supercritical aperture.  For group photos you could use an extra flashgun and the camera
will increase the shutter speed as you set before the lowest shutter speed
during the use of flashgun but in other segments of photography you cannot use
the flashgun. Basically, you should think about the shutter speed according to
your aperture setting. Night time recommendation is open aperture and also open aperture
lenses for the shutter speed. Not only the shutter speed but the open aperture
lenses allow maximum light to the sensor. Avoid increasing ISO because it will
reduce the sharpness of the images, use prime lenses instead of using zoom
lenses. For the prime lenses after the super critical aperture of a lens
the sharpness or the DOF area starts to reduce. After the super critical
aperture as much as you increase the f value it will be softer than the
previous setting. So, try to shoot in critical or supercritical aperture when
you get the enough light source. Night time for the DX format body you may
increase the ISO up to 400 but not more than that.
Practise
with different depth of subjects and adjust the aperture accordingly, within a
short time you will be the master of it. Technibas always wants to hear from
your side. Leave your valuable opinion in the comment section. Follow us on
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Enjoy clicking, keep clicking & safe clicking |
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